Accounting for Imported Cases in Estimating the Time-Varying Reproductive Number of Coronavirus Disease 2019 in Hong Kong. (4th June 2021)

• Record Type: Journal Article
• Authors: Tsang, Tim K; Wu, Peng; Lau, Eric H Y; Cowling, Benjamin J
• Is Part Of: Journal of infectious diseases. Volume 224:Number 5(2021)
• Page Start: 783
• Page End: 787
• Publication Date: 2021-06-04
• Subjects: reproductive number -- COVID-19 -- transmissibility -- imported cases; Communicable diseases -- Periodicals; Diseases -- Causes and theories of causation -- Periodicals; Medicine -- Periodicals; Communicable Diseases -- Periodicals; Electronic journals; 616.9
• DOI: 10.1093/infdis/jiab299
• Languages: English
• ISSNs: 0022-1899

Abstract

Abstract: Estimating the time-varying reproductive number, R t, is critical for monitoring transmissibility of an infectious disease. The impact of imported cases on the estimation is rarely explored. We developed a model to estimate separately the R t for local cases and imported cases, accounting for imperfect contact tracing of cases. We applied this framework to data on coronavirus disease 2019 outbreaks in Hong Kong. The estimated R t for local cases rose above 1 in late March 2020, which was undetected by other commonly used methods. When imported cases account for a considerable proportion of all cases, their impact on estimating R t is critical. Abstract : We developed a model to estimate separately the time-varying reproductive number (R t ) for local cases and imported cases, accounting for imperfect contact tracing of cases, and potential different infectiousness among local and imported cases.